Courtesy Laura Smith(AURORA, Colo.) -- When Laura Smith entered the Natural Healing Center in Aurora, Colo., last month, she was hoping for a massage to relieve the aftereffects of a half-marathon she had run the day before.

"I ran 21.1 miles. I was hurting just from that in and of itself," Smith, 31, said. "I was really looking forward to the massage. I was going to relax."

Instead of leaving with soothed muscles, she instead got a bruised ego after being turned down because of her weight. "She [the owner of Natural Healing Center] was very matter of fact about it. She said, 'I'm really sorry, but you're just too fat for our table. You'll probably break [it] and have to pay for it.'"

Such a dismissal caught Smith, who is 6-foot-3 with an athletic build, off-guard. Having received many massages before at other spas, even before she lost almost 50 pounds to put her at 250 pounds, her size had never been an issue.

"I was just kind of in shock," she recalled of the Jan. 31 incident. "When it sunk in, I just started to cry, then I grabbed my stuff and left."

When Smith later called back, she said she learned that the tables were designed to support up to 500 pounds. Penny Wells, the owner of the Natural Healing Center, later told local media that a table had recently broken under a 165-pound man, which is why she was worried about Smith.

Wells has not responded to an ABC News request for comment.

Weight discrimination is hardly new, but studies suggest that it is an ongoing problem. The 2008 issue of the International Journal of Obesity states that weight discrimination "occurs in employment settings and daily interpersonal relationships virtually as often as race discrimination, and in some cases even more frequently than age or gender discrimination."

"I shouldn't have to expect to be treated poorly," Smith said. "I just ran a half-marathon. I just did something amazing. For somebody to be rude to me after that is just not OK."

But many people immediately rushed to her defense. Hundreds of people posted their support to her Facebook testimony of what happened. Overweight to Endurance Athlete, a program to which she belongs that focuses on teaching overweight people healthy lifestyles, was overwhelmed with public outcry.

"She couldn't believe that people who hadn't even met her were encouraging her," friend and program coach Kristen Schuldt said. "It was heartbreaking to see somebody get hurt like that but all of the support I think helped lift her up and give her some inspiration."

Rather than allowing the incident to deter her, Smith is instead using it as an opportunity to bring attention to the issue and use it as motivation.

"I just want to be a voice for people who haven't been able to speak up for themselves or who are afraid to," she said. "It could have been detrimental. It could have made me depressed.

"But now [during] the moments that I don't want to go to the gym, I just think about the time somebody told me that I'm too fat to do something," she added. "I just think, 'I better get out of bed. I have another 5K to run.'"